Apparatus for applying a surface pattern on boards of wood, fiberboard, or the like



March 16, 1965 u. STANDFUSS 3,173,804

APPARATUS FOR APPLYING A SURFACE PATTERN ON BOARDS 0F WOOD, FIBERBOARD, OR THE LIKE Filed Dec. 13, 1961 2 Sheets-Sheet l 3,1 73, RDS

March 16, 1965 u. STANDFUSS APPARATUS FOR APPLYING A SURFACE PATTERN ON BOA OF WOOD, FIBERBOARD, OR THE LIKE 2 Sheets-Sheet 2 Filed Dec. 13, 1961 ji y Ulrich STANDFUSS United States Patent Ofi ice 3,173,864 APPARATUS FGR APPLYNG A SURFAQE FAT- TERN N BOARDS OF WGOD, FIBERBOARD, QR THE LIKE 3 Claims. bi. rrs 4s The present invention relates to an apparatus for ap plying a surf-ace pattern directly to boards or sheets of wood, fiberboard, press'ooard, or the like.

In the furniture manufacture of the prior art the operation of coating the individual parts of a piece of furni ture could not be carried out until they were assembled and secured to each other to form the complete article. The principal reason for this manner of production was the fact that it was practically impossible to carry out the assembly and fitting operations Without damaging the finished surfaces of the individual parts.

It is therefore an object of the present invention to pro vide the individual parts of furniture articles, made of wood, fiberboard, pressboard, or the like, prior to their assembly with a coating and surface pattern which is so permanent and resistant that there is practically no danger that this coating will be marred by the manipulations of assembling these parts into the finished furniture articles. Another object of the invention is to provide an apparatus for producing individualized coatings on lino-cellulose sheets having fancy imprints and a durable hard surface, by mass production means.

Another object of the invention is to coat the component parts prior to prefabrication of the individual furniture parts by mass production methods to render the furniture manufacture considerably more economical.

Still another object of the invention is to improve the quality of the coating and to render the new method still more economical.

Another object of the invention is to provide a suitable apparatus for carrying out the numerous steps thereof in a continuous movement through the various treating stages in a manner utilizing same stages and parts to function in plural capacities, to save expense and time in mass production.

The above and various other objects, features, and advantages of the present invention will become more closely apparent from the following detailed description thereof which is to be read with reference to the accompanying drawings of a preferred apparatus for carrying out the new method, in which like reference numerals designate like parts throughout the figures thereof and wherein FIGURE 1 shows a perspective view of a first part of the apparatus for carrying out the new method.

FIGURE 2 shows a perspective view of the second part of the apparatus which directly follows the part as illustrated in FIGURE 1;

FIGURE 3 shows a perspective view of a board as produced according to the inventive method; while FIGURE 4 shows a cross section of a board according to FlGURE 3 and it also indicates on a magnified scale the individual coatings on the surface of the board.

The apparatus in a preferred embodiment illustrated in the drawings comprises several conveyor belts which are arranged relative to each other to permit a continuous movement of the boards or sheets 1 through the difierent work stages required. A succession of chambers separated from each other by partitions and closed by front and rear walls is provided for the various steps of the process.

3,173,8M Patented Mar. 16, 1965 The front walls are shown removed from the chambers. Some of the conveyors are utilized simultaneously to function as the bottoms of the chambers. The functions which are to be carried out at the different work stages and by the individual conveyor belts, will become apparent from the following description of the entire method.

The A stage The boards are precut with their still rough outer surfaces to the required size. The precut parts 1 are loaded, as shown at A in FIGURE 1, upon a first conveyor belt 2 in the embodiment shown. The belt carries the boards into a pro-treating chamber 5 in which their upper surfaces are treated by brushes 6. The brushed boards 1 are then carried into a preheating chamber 7 in which their upper surfaces are preheated to a first temperature between 50 and 108 C. Chamber 7 is for this purpose equipped with suitable heating means 8, connected with a heat source, not shown, through a line 9. The preheating source may be, among others, hot water, hot

ir, dielectric or infrared radiators or others. In the preheating chamber, a fluid priming mixture is applied upon the boards by means of a feeding and doctor unit 11. The priming mixture has a content of resin and solvents permitting first the formation of a soft layer on the upper surface of the boards. The heat of the preheating chamber dries the priming mixture from the bottom. The board is carried next through an evaporating chamber 12 and a drying chamber 13. The first prime coat is formed on the boards after the solvent has been evaporated in the chambers 12 and 13 and when this layer has thus been dried. The solvent is drawn off from chamber 12, through the outlet line 14- together with hot air of a second temperature of about 40 to 50 C. supplied into chamber 12 through a line 15 in the direction of movement of plates 1. The solvent thereafter may be separated from the gas or steam passing out of chamber 12 through line to, for the purpose of recovering it for future use.

By heating the surface of the boards before applying the prime coat thereon, the heat required for evaporating the solvent from the prime-coating materials will, at least to a considerable extent, be furnished by the heat content of the surface of the boards and the prime coat will thus be dried primarily from below rather than from above, that is, by the board surface which has been preheated to the required temperature.

The mixtures which are employed according to the invention for producing the prime coats and the outer paint or varnish coating may consist of co-polymers, aminoplasts, for example, urea melamine resins, or oil modified alkyd resins, and the respective solvents for these materials, aside from the pigments and dulling agents which are required for the surface pattern and depend upon the desired type thereof. Although the paints or varnishes employed for the prime coats start to polymerize at a relatively low temperature, their final complete polymerization occurs when the outer coating is baked in.

After leaving the chamber 12, boards 1 press into the drying chamber 13 which may be of the same construction as the preheating chamber 7 with a similar heat supply. Hot-water radiators have the considerable advantage that they heat the surface of the boards very uniformly and thus prevent the danger of blister-forma tions. In addition, the drying chamber 13 is connected by lines 15 and 14 with a hot air supply of a temperature of about C. or more, circulated through chamber 13 in a direction opposite to the direction of movement of boards 1 on the conveyor belt 2.

The boards 1 leaving the drying chamber 13 then enthe above mentioned chambers. erations of the second .priming are carried out precisely amasoa ter the cooling chamber 16 through which cooling air of a normal room temperature is blown from above upon the upper surface of the boards through nozzles, not shown mounted on the inner ends of air feed lines 17.

This completes the operations of providing boards 1 with the first prime coat. After the first prime coat has been applied and been cooled to room temperature, the coated surface of the boards is ground. This also improves the durability of the outer coating and the appearance of the finished boards. The boards pass on the first conveyor belt out of chamber 16 to drop upon a second conveyor belt 18 which carries them toward and deposits them on 'a third conveyor belt 19. By a conventional transfer means, not shown, the boards there are removedto a work table 20, for a grinding operation by hand. Of course, the apparatus may also be provided with a grinding mechanism, not shown, which grinds the surface of boards 1 mechanically While they are moving on the conveyor belt 19.

' The B stage carried out by means of a separate fifth conveyor belt 22 which runs parallel to and in the same direction as the first belt 2. The boards are thus treated once more in the same maner as during their first passage through Since the successive opas those of the first priming, they do not need to be again described. 7

The dots on thesurfaces of boards 1 on belt 22. in FIGURE 1 serve to indicate the different surface treatments to which the boards are being subjected. Thus,

while the boards on conveyor belt 2 are plain up to chamber to indicate that they are as yet uncoated, the subsequent light dotting of boards 1 on conveyor belt 2 beg-inning in' chamber 10 indicates that they have been provided with a single prime coat, while the parallel heavily dotted boards 1 on conveyor 22 indicate that these boardshave received two prime coats.

The C stage The twice prime-coated boards are carried to a station C by conveyor belts 24 and 25, shown in FIGURES l and 2, and by further conveying means indicated diagrammatically in FIGURE 2 by an arrow, these various This movement of the once-coated V boards through the apparatus is, however, preferably tern effects maybe attained if the surface, after being printed with oil paint and before the liquid resin mixture for the final baked-in coating is applied, is merely surface-dried. This has the result that the paint which is not as yet fully dry will slightly run on the surface of the boards when the liquid resin mixture is subse quently applied. In this manner, it is possible to produce a surface pattern which closely resembles the grain of natural plywood. In order to attain a high gloss, the

printed surfaces may in addition he passed over calendar rolls-which may be either heated or unheated. At station C, the boards are automatically transferred to a seventh conveyor belt 26 and are then at first passed 1nto an offset printing mechanism This mechanism comprises a paint roller 27, a transfer roller 2%, and a soft-rubber roller 29. This last roller 29 is designed for applying a printed pattern, for example, similar to the natural grain of wood, upon the surface of the boards. More than one printing stage may be applied in succession, for

' eference to chambers '7 and 13 merely serve for drying the ink or paint coating of the pattern to some extent. In the following chamber 31 a fluid resin mixture is then applied upon the boards by means of a feeding and doctor unit 32. This resin mixture which subsequently forms the outer coating of the boards is made of such a composition that, after its subsequent treatment, it forms a high-grade baking enamel. Chambers 3-3 and se through which the boards are then moved are of substantially the same construction and serve substantially the same purpose as chambers 12 and 13, and they are therefore also provided with inlet and outlet lines 15 and 14 for pressing hot air of about 40 to 50 C. through these chambers and thereby also withdrawing the solvent vapors therefrom.

The D stage After boards 1 have thus been superficially dried and have left the chambers 34, they are deposited upon another conveyor belt 35 and are transferred thereby to a further conveyor belt 36 which passes through baking oven 37. There the surface of the boards is heated to a third temperature between and C for bakingin the outer predried enamel coating. The heating means for the oven chamber 37 may consist, for example, of infrared radiators 38 which are mounted above boards 1.

From the oven chamber 37, the boards 1 are carried into a cooling chamber 39 which is similar to chamber 16 of the prime-coating part of the apparatus.

The finished boards 1 may' then be removed from the conveyor belt 35 near its end D. If desired, they may thereafter be passed to a humidifying apparatus, not shown, in which the inner structure of the boards is given a certain moisture content, or they may for the same purpose be passed over so-called moistening rolls.

The boards which have been dried out considerably by the different heat treatments and especially by the last baking treatment, are thus given again a certain moisture content whereby difficulties in the subsequent use of the boards, for example, in their assembly into furniture articles, will be avoided. If the dried out board-s would be used immediately, the furniture pieces might subsequently warp because of the absorption of moisture.

If the boards are to be provided with a surface pattern on both sides, they should first be run with the unooated side over the moistening roll before the patternis also applied on that side.

FIGURE 4 illustrates diagrammatically a board 1 which has been treated in accordance with the invention and in which 40 indicates the board itself, 41 the first prime coat, 42 the second prime coat, 43 the printed pattern, and 44 the router coating.

The boards or the like are in this manner provided with a coating of a solidity similar to that of the enamel coatings on sheet metal and solid metal parts of automobile bodies. The method according to the invention is therefore especially of importance in the manufacture of furniture which has to withstand hard usage, for example, childrens furniture.

Although my invention has been illustrated and described with reference to the preferred embodiments thereof, I wish to have it understood that it is in no way limited to the details of such embodiments, but is capable of numerous modifications Within the scope'of the appended claims.

encased Having thus fully disclosed my invention, what 1 claim is:

1. An apparatus for treatment of rough surfaced sheets of linocellulose to provide them with fancy designs and a hard baked enamel coat comprising a first section for coating the surface, including an inlet and an outlet station and a plurality of compartments ali ned in longitudinal succession and equipped in succession, respectively with means to preheat said sheets to a first temperature between 50 C. to ill-3 C. means to apply a fluid coat to the preheated sheets in a first compartment and to press the fluid coating into the pores and interstices of the rough surface of said sheets, at least one second compartment with means to heat the coated surface to a second temperature of about 4% to 50 C., calculated to evaporate the fluid coat Without blistering it, at least one third compartment with means to heat the surface to a third temperature of at least 120 C. calculated to dry the said coat, at least one fourth cooling compartment with means to cool the dried coat, a fust conveyor means running longitudinally underneath said first to fourth compartments to transport the sheets from said inlet station through said compartments to said outlet station; a second conveyor means conveying said sheets from said outlet station and a conveyor for conveying said sheets to said inlet station; a third conveyor means running longitudinally underneath said first to fourth compartments in parallel alignment and adjacent with said first conveyor means to transport said coated sheets again through said first to fourth compartments, said first to fourth compartments having a width at least equal to the combined Width of said first and said third conveyor means, said conveyor means being endless belts and forming a moving bottom of said first to fourth compartments; a second section for offset printing said coated surfaces, comprising a printing means including a paint roller, a transfer roller and a pattern roller-printer, and at least one heating compartment for drying the print; a third section for print-fixing the printed surface, comprising a compartment with means to apply an outer coating of a fluid resin mixture in an even distribution thereof over said surface, and at least one heating compartment with means to supply heat of about 40 to 50 C. calculated to with draw vapors of said resin; said second and third sections being in longitudinal alignment; a fourth conveyor means for transporting said sheets from said first sec tion to said second section; a fifth conveyor means running underneath said second and third sections and forming a moving bottom thereof; and a fourth section for baking said outer coat to a hard enamel comprising at least one baking compartment with means to supply a heat of about 12 to 186 C., calculated to bake the printed coated surface to a hard enamel, a cooling compantment and conveyor means forming the bottom of said compartments.

2.. An apparatus for treatment of sheets of linocellulose to provide them with fancy designs and a hard baked enamel coat comprising, a first section for coating the surface, including an inlet and an outlet station and a plurality of compartments aligned in longitudinal succession and equipped in succession, respectively, with means to preheat said sheets to a first preheating temperature, means to apply a fluid coat to the preheated sheets having rough surfaces in a first coating compartment and to press the fluid coating into the pores and interstices in the rough surface of said sheets, at least one second com partment with means to heat the coated surface to a second temperature evaporating the fluid coat, at least one third compartment with means to heat the surface to a third drying temperature of the said coat, at least one fourth cooling compartment With means to cool said surface, a first conveyor means running longitudinally underneath said first to fourth compartments to transport the sheets from said inlet station through said compartments to said outlet station; a second conveyor means conveying said sheets from said outlet station and a conveyor for conveying said sheets to said inlet station; said first to fourth compartments having a Width at least equal to the Width of said first conveyor means said first conveyor means forming an endless belt and a moving bot tom of said first to fourth compartments; a second section for printing said coated surfaces, comprising a printing means, and at least one heating chamber for drying the print; a third section for print-fixing the printed surface, comprising a compartment with means to apply an outer coating of a fluid mixture and an even distribution thereof over said surface and at least one heating chamher with means to supply heat calculated to Withdraw vapors of said resin; said second and third sections being in iOllgltLlCill'lfii alignment; a conveyor means for transporting said sheets from said fi st section to said second section; a conveyor means running underneath said second and third sections and forming a moving bottom thereof; a fourth section for baking said outer coat to a hard enamel comprising at least one baking compartment With means to supply a heat calculated to bake the printed coated surface to a hard enamel, a cooling compartment and conveyor means forming the bottom of said cornpartmcnts.

3. An apparatus for treatment of sheets of linocellulose to provide them with fancy designs and a hard baked enamel coat comprising a first section for coating the surface, including an inlet and an outlet station and a plurality of compartments aligned in longitudinal succession and equipped in succession respectively, with means to preheat said sheets, means to apply a fluid coat to the preheated sheets having rough surfaces in a first coating compartment, and to press the fluid coating into the pores and interstices in the rough surface of said sheets, at least one second compartment with means to heat the coated surface to a second temperature calculated to evaporate the fluid coat without blistering it, at least one third compartment with means to heat the surface to a third temperature calculated to dry the said coat, at least one fourth cooling compartment with means to cool said surface, a first conveyor means to transport the sheets from said inlet station through said compartments to said outlet station; a second section for printing said coated surfaces, comprising a printing mechanism and at least one heating chamber for drying the print; a third section for print-fixing the printed surface, comprising a compartment with means to apply an outer coating of a fluid resin mixture and an even distribution thereof over said surface, and at least one heating chamber with means calculated to Withdraw vapors of said resin; a conveyor means for transporting said sheets from said first section through said second and third sections; a fourth section for baking said outer coat to a hard enamel comprising at least one baking compartment with means to supply heat and cooling compartment.

References Cited by the Examiner UNITED STATES PATENTS RICHARD D. NEVIUS, Primary Examiner.

JOSEPH B. SPENCER, Exan'zincr. 

1. AN APPARATUS FOR TREATMENT OF ROUGH SURFACED SHEETS OF LINOCELLULOSE TO PROVIDE THEM WITH FANCY DESIGNS AND A HARD BAKED ENAMEL COAT COMPRISING A FIRST SECTION FOR COATING THE SURFACE, INCLUDING AN INLET AND AN OUTLET STATION AND A PLURALITY OF COMPARTMENTS ALIGNED IN LONGITUDINAL SUCCESSION AND EQUPPED IN SUCCESSION, RESPECTIVELY WITH MEANS TO PREHEAT SAID SHEETS TO A FIRST TEMPERATURE BETWEEN 50*C. TO 100*C. MEANS TO APPLY A FLUID COAT TO THE PREHEATED SHEETS IN A FIRST COMPARTMENT AND TO PRESS THE FLUID COATING INTO THE PORES AND INTERSTICES OF THE ROUGH SURFACE OF SAID SHEETS, AT LEAST ONE SECOND COMPARTMENT WITH MEANS TO HEAT THE COATED SURFACE TO A SECOND TEMPERATURE OF ABOUT 40* TO 50* C., CALCULATED TO EVAPORATE THE FLUID COAT WITHOUT BLISTERING IT, AT LEAST ONE THIRD COMPARTMENT WITH MEANS TO HEAT THE SURFACE TO A THIRD TEMPERATURE OF AT LEAST 120*C. CALCULATED TO DRY THE SAID COAT, AT LEAST ONE FOURTH COOLING COMPARTMENT WITH MEANS TO COOL THE DRIED COAT, A FIRST CONVEYOR MEANS RUNNING LONGITUDINALLY UNDERNEATH SAID FIRST TO FOURTH COMPARTMENTS TO TRANSPORT THE SHEETS FROM SAID INLET STATION THROUGH SAID COMPARTMENTS TO SAID OUTLET STATION; A SECOND CONVEYOR MEANS CONVEYING SAID SHEETS FROM SAID OUTLET STATION AND A CONVEYOR FOR CONVEYING SIAD SHEETS TO SAID INLET STATION; A THIRD CONVEYOR MEANS RUNNING LONGITUDINALLY UNDERNEATH SAID FIRST TO FOURTH COMPARTMENTS IN PARALLEL ALIGNMENT AND ADJACENT WITH SAID FIRST CONVEYOR MEANS TO TRANSPORT SAID COATED SHEETS AGAIN THROUGH SAID FIRST TO FOURTH COMPARTMENTS, SAID FIRST TO FOURTH COMPARTMENTS HAVING A WIDTH AT LEAST EQUAL TO THE COMBINED WIDTH OF SAID FIRST AND SAID THIRD CONVEYOR MEANS, SAID CONVEYOR MEANS BEING ENDLESS BELTS AND FORMING A MOVING BOTTOM OF SAID FIRST TO FOURTH COMPARTMENTS; A SECOND SECTION FOR OFFSET PRINTING SAID COATED SURFACES, COMPRISING A PRINTING MEANS INCLUDING A PAINT ROLLER, A TRANSFER ROLLER AND A PATTERN ROLLER-PRINTER, AND AT LEAST ONE HEATING COMPARTMENT FOR DRYING THE PRINT; A THIRD SECTION FOR PRINT-FIXING THE PRINTED SURFACE, COMPRISING A COMPARTMENT WITH MEANS TO APPLY AN OUTER COATING OF A FLUID RESIN MIXTURE IN AN EVEN DISTRIBUTION THEREOF OVER SAID SURFACE AND AT LEAST ONE HEATING COMPARTMENT WITH MEANS TO SUPPLY HEAT OF ABOUT 40* TO 50*C. CALCULATED TO WITHDRAW VAPORS OF SAID RESIN; SAID SECOND AND THIRD SECTIONS BEING IN LONGITUDINAL ALIGNMENT; A FOURTH CONVEYOR MEANS FOR TRANSPORTING SAID SHEETS FROM SAID FIRST SECTION TO SAID SECOND SECTION; A FIFTH CONVEYOR MEANS RUNNING UNDERNEATH SAID SECOND AND THIRD SECTIONS AND FORMING A MOVING BOTTOM THEREOF; AND A FOURTH SECTION FOR BAKING SAID OUTER COAT TO A HARD ENAMEL COMPRISING AT LEAST ONE BAKING COMPARTMENT WITH MEANS TO SUPPLY A HEAT OF ABOUT 120* TO 180*C., CALCULATED TO BAKE THE PRINTED COATED SURFACE TO A HARD ENAMEL, A COOLING COMPARTMENT AND CONVEYOR MEANS FORMING THE BOTTOM OF SAID COMPARTMENTS. 